系统误差

As the choice of Neural Network will directly affect the detection data, BP based system is constructed by error reversion algorithm to train itself. It is simper and faster than other type of system.

由于系统所采用的神经网络的类型将直接影响数据检测结果的准确性，而BP神经网络是以误差反向传播算法对网络进行训练，其结构简单、收敛速度快；RBF 神经网络以简单变量的参数组合为函数来实现，具有训练速度比较快、性能比较好的特点。

The experiment shows that the proposed method can reflect the countermeasure effect of smoke screen on infrared imaging tracker exactly, and is an effective evaluation method.

仿真实验表明，基于分形拟合误差的评估方法能够真实地反映烟幕对红外成像跟踪系统的干扰效果，是一种有效的评估方法。

Adopt the arithmetic of synchronization disturbance random approach presented by Spall to train the Neural Network Controller by the output error of system.

采用Spall［1］提出的同步扰动随机逼近的算法，通过系统的输出误差对神经网络控制器进行训练。

Aiming at the disadvantage of conventional BP neural network, such as selecting parameter values by the empirical method, slow convergence speed and easy trap into local minimum points, this paper designs an improved BP neural network system. In order to improve the network convergence rate and reduce the training error, this paper optimizes the initial connecting weight value of neural network by the use of ant colony algorithm and trains artificial neural network by Levenberg-Marquardt algorithm.

针对常规BP神经网络参数的经验式取值方法以及收敛速度慢，容易陷入局部最小点等缺陷，设计了一种改进的神经网络系统，利用蚁群算法优化神经网络连接权初值，并采用LM算法对人工神经网络进行训练，提高了网络的收敛速度，降低了训练误差。

The scheme can effectively correct the static errors in the magnetic tracking system. The employment of spherical coordinates significantly reduces the calculation complexity in calibration.

此方法能够有效地校正电磁跟踪系统中的静态误差，通过应用球坐标系显著地降低校正计算的复杂程度。

During the process of state estimation, recursive extended least square was introduced to update the parameters of state model, at the same time exponential weighted algorithm was put in use to estimate the statistical characteristic of time-varying noise.

这样，在利用量测数据进行状态估计的同时，来不断的对系统模型参数和噪声统计特性进行估计和修正以提高模型精确度，降低状态估计的误差。

The simulation results demonstrated the algorithm is stable, convergent and fair, and robust with respect to variants of stochastic delay and stochastically accessed users.

仿真证明，算法保证了闭环系统的稳定性、收敛性和公平性，对传输延迟的时变特性和用户的动态变化引起的测量误差具有较好的鲁棒性。

The system structure and the mathematic model of least square method to evaluate the straightness errors are introduced.

介绍了系统结构原理以及空间直线度误差的最小二乘评定法数学模型。

With the amplitude and phase compensation method,the compensation function is developed by the stroboscope analysis of import signal and frequency characteristic identification of production system.

幅度相位补偿法能通过对原输入信号的频谱分析和对加工系统的频率特性辨识来确定补偿函数，经补偿后的输入信号能明显改善活塞的误差曲线，从而提高活塞的加工精度。

On this basis, we consider a class of suboptimum detectors for the asynchronous SSMA system whose decision algorithms consists of a linear transformation followed by a set of threshold devices.

在此基础上，针对随机多址扩频通信系统的情况，分别提出了两种线性检测器—最小均方误差检测器和加权最小平方检测器，以及一种非线性检测器—判决反馈检测器，给出了它们的实现原理和方法。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。